The right monitor of my PFE's has been acting up lately. I took it out to listen one day and I noticed that the right monitor didn't play any music, so I left it on my desk for a couple of days. I used them again just 4 days ago and I found that the right monitor came back to life. I took them on a trip to Chicago today and they worked fine, but I noticed that the right monitor was decreasing in volume over time. On the way back, I plugged them in again and I noticed that the right monitor wasn't playing music again. How do I save my PFE's?